title: The effects of lipoic acid and α-tocopherol supplementation on the lipid profile and insulin sensitivity of patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled trial.
abstract: Antioxidants probably play an important role in the etiology of type 2 diabetes (DM2). This study evaluated the effects of supplementation with lipoic acid (LA) and α-tocopherol on the lipid profile and insulin sensitivity of DM2 patients. A randomized, double-blind, placebo-controlled trial involving 102 DM2 patients divided into four groups to receive daily supplementation for 4 months with: 600 mg LA (n = 26); 800 mg α-tocopherol (n = 25); 800 mg α-tocopherol + 600 mg LA (n = 25); placebo (n = 26). Plasma α-tocopherol, lipid profile, glucose, insulin, and the HOMA index were determined before and after supplementation. Differences within and between groups were compared by ANOVA using Bonferroni correction. Student's t-test was used to compare means of two independent variables. The vitamin E/total cholesterol ratio improved significantly in patients supplemented with vitamin E+LA and vitamin E alone (p ≤ 0.001). There were improvements of the lipid fractions in the groups receiving LA and vitamin E alone or in combination, and on the HOMA index in the LA group, but not significant. The results suggest that LA and vitamin E supplementation alone or in combination did not affect the lipid profile or insulin sensitivity of DM2 patients.
authors.affiliation: Department of Nutrition, School of Public Health, University of São Paulo, São Paulo, Brazil.
authors.forename: Andreia Madruga
authors.initials: AM
authors.lastname: de Oliveira
authors.forename: Patrícia Helen Carvalho
authors.initials: PH
authors.lastname: Rondó
authors.forename: Liania Alves
authors.initials: LA
authors.lastname: Luzia
authors.forename: Francisco Homero
authors.initials: FH
authors.lastname: D'Abronzo
authors.forename: Vanessa Kristine
authors.initials: VK
authors.lastname: Illison
mesh_terms: D000328:Adult; D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D008063:Thioctic Acid / Q000627:therapeutic use*; D024502:alpha-Tocopherol / Q000627:therapeutic use*
chemical_list: D007328:Insulin; D008055:Lipids; D008063:Thioctic Acid; D024502:alpha-Tocopherol